Motor fuel



Patented May 18, 1937 PATENT OFFICE MOTOR FUEL Jesse Russell Wilson, Chicago, Ill., and Vanderveer Voorhees, Hammond, Ind., assignors to Standard Oil Company, Chicago, 111., a corporation of Indiana No Drawing. Application July 28, 1933, Serial No. 682,667

12 Claims.

This invention relates to an improved motor fuel and it pertains more particularly to a motor fuel containing a gum flux.

Motor benzol, and particularly cracked gasolines, contain large quantities of unsaturated hydrocarbons such as the oleflns and diolefins. When such motor fuels are stored for relatively short periods of time, the unsaturated hydrocarbons oxidize and/or polymerize and form gum. Some of the gum that forms during storage precipitates whereas a large part of the gum remains dissolved and/or suspended in the gasoline. When a cracked gasoline, containing dissolved or suspended gum, is used in an internal combustion engine, the gum deposits on the valves, in the cylinders and in the fuel induction system when the fuel is vaporized. The fraction of gum that deposits in the cylinders is soon carbonized on the pistons and valves, thereby greatly impairing the efliciency of the engine and causing the valves to stick.

The object of our invention is to provide a motor fuel which contains a solvent or gum flux that has a selective solvent action on gasoline gum and will prevent or greatly retard the precipitation of gum in the fuel system of the englne.

A particular object of our invention is to provide a motor fuel with a gum flux which will retard the precipitation of gum and the formation of hard carbon deposits in the cylinders of internal combustion engines.

The gums formed by the oxidation and/or polymerization of the unsaturated constituents in motor fuels have high molecular weights and are substantially insoluble in petroleum hydrocarbons after they have once deposited and been subjected to heat. In fact, they form a varnishlike coating which may become insoluble in any known organic solvent if not removed before polymerization has proceeded too, far. We have found that normally liquid aromatic hydrocarbons having a boiling point above 450 F. and preferably above 500 F. may be dissolved in gummy motor fuels in quantities ranging from 0.2% to 2% and thereby prevent or greatly retard the precipitation of gum on the valves and in the cylinders of internal combustion engines. The presence of an' aromatic gum flux in the motor fuel prevents the gums'from being carbonized and reduced to a hard coke by removing them before they have become too highly polymerized. Consequently the valves remain free acting and the operation of the engine is not impaired. In-order to obtain really effective results from the use of a gum flux of this type, it is necessary to have it continually present during the operation of the engine, as otherwise the deposited gum rapidly hardens and cannot be removed. One of the essential and unique characteristics of our flux is its low volatility combined with high solvent power which enables it to act as a liquid flux at relatively high engine tem'- peratures whereas gum solvents commonly used heretofore have been of the volatile type having good solvent power for the gum but incapable of exerting its action during the operation of the engine at the critical time when the gum is being deposited and polymerized.

The gum solvents used in our invention are soluble in cracked gasoline. The gum flux should normally be liquid so that it does not crystallize at low seasonal temperatures and We make use of mixtures of different fluxes to obtain still lower freezing points. Most of the gum fluxes are normally liquid, high boiling, carbo-cyclic aromatic hydrocarbons. The boiling point of the flux should be well above the end boiling point of the gasoline so that the flux will be sprayed into the manifold and cylinders'in the form of a mist. Generally, compounds boiling between 500 and 600 F. are preferable, but compounds boiling as low as 450 F. may be used with a reasonable degree of success. Examples of the compounds which may be used for our invention are: Orthometaand para-phenyl toluene, dihydro ethyl anthracene, alpha methyl naphthalene, 1-4 dimethyl naphthalene, alpha and beta ethyl naphthalene, alkyl naphthalenes, beta-n-propyl naphthalene, alpha-n-propyl naphthalene, al-

pha-n-butyl naphthalene, beta-,n-butyl naphthalene, alpha and beta phenyl naphthalenes, actetra beta naphthol, ethyl benzyl benzene and alpha diphenyl ethane. Mixtures of the above compounds may be used.

By dissolving about 0.2 to 2% of one or a mixture of the compounds set forth in the above groups in gasoline, the formation of hard carbon deposits in the engine can be greatly reduced by an amount of about -80%. However, the amount of carbon formed will depend somewhat upon the type of motor fuel used. In addition to the elimination of carbon in internal combustion engines, the gum fluxes tend to stabilize the color of cracked gasoline and prevent sedimentation during storage.

If desired, antioxidants may be used in comsuch as catechol, anthraquinone and pyrogallol; aminophenols such as ortho-metaand para aminophenol, para-phenyl aminophenol, methyl aminophenols. phenyl aminophenols, para-ben- 7. A motor fuel comprising cracked gasoline containing non-volatile gum which deposits in the cylinders of the motor and containing, as a gum flux, from 0.2 to 2% of a normally liquid 5 zyl aminophenol and the like. alkylated naphthalene compound having a boil- 5 We claim: ing point above 500 F.

1. A motor fuel comprising cracked gasoline 8. A motor fuel comprising gasoline containcontaining non-volatile gum which normally ing a non-volatile gum dissolved therein which tends to deposit on the valves and in the cylinnormally tends to deposit in the cylinders of the ders of the motor and containing, as a gum flux, motor and containing, as a gum flux, from about 10 from 0.2 to 2% of a normally liquid carbocyclic 0.2 to 2% of a normally liquid alkylated naphhydrocarbon having a boiling point above 450 F. thalene hydrocarbon having a boiling point above 2. A motor fuel comprising unsaturated hyabout 500 F. drocarbons and containing non-volatile gum A mo or fuel comprising gasoline containwhich deposits on the valves and in the cylin- 111g a -Vo a e gu d ssolved therein Which 5 ders of the motor and containing, as a, gum flux, normally tends t0 deposit in the cylinders of the from 0.2 to 2% of a normally liquid carbo-cyclic 0130 and Co s a gum flux, from ab t hydrocarbon having a boiling point between 450 t o a normally liquid naphthalene and 600 F. drocarbon having at least one alkyl group con- 3. A motor fuel comprising gasoline with a taining from two to four carbon atoms attached 20 non-volatile gum dissolved therein which norto the naphtha e ring and Said o p d mally tends to deposit on the valves and in g aboiling point above 0 F- the cylinders of the motor and containing, as a A O fuel Comprising a o Co ingum flux, from 0.2 to 2% of a normally liquid ing a non-volatile gum dissolved therein which carbo-cyclic hydrocarbon having a boiling point normally tends to d p in the cylinders of the 25 between 500 and 600 F. motor and containing, as a gum flux, from 0.2

4. A motor fuel comprising unsaturated gasoto 2% of a normally liquid methyl naphthalene line containing non-volatile gum which normalhydrocarbon having a boiling point above 450 F. 1y deposits on the valves and in the cylinders of A 1110 50 fuel Comprising gasoline Conta the motor and containingas a gum flux, from ing a non-volatile gum dissolved therein which 30 0.2 to 2% of a normally liquid naphthalene hynormally tends to deposit in the cylinders of the drocarbon having a boiling point above 450 F. motor and containing, as a gum flux, from 0.2 to

5. A motor fuel comprising unsaturated gaso- 2% of a normally ethyl naphthalene hydrocarline containing non-volatile gum which deposists bon having a boiling point above 450 F.

on the valves and in the cylinders of the motor 12. A motor fuel comprising gasoline contain- 35 and containing, as a gum flux, from 0.2 to 2% ing a non-volatile gum dissolved therein which of a normally liquid naphthalene hydrocarbon normally tends to deposit in the cylinders of the having a boiling point between 500 and 600 F. motor and containing, as a gum flux, from 0.2

6. A motor fuel comprising cracked gasoline to 2% of a normally liquid alkylated naphthalene 4a which contains non-volatile gum that deposits hydrocarbon wherein the alkyl group contains on the valves and in the cylinders of the motor and containing, as a gum flux, from 0.2 to 2% of a normally liquid alkylated naphthalene hydrocarbon having a boiling point above 450 F.

from three to four carbon atoms, said alkylated hydrocarbons having a boiling point above 450 F.

VANDERVEER VOORHEES. JESSE RUSSELL WILSON.

CERTIFICATE OF CORRECTION Patent No. 2.080,68l May 18, 1937.

JESSE RUSSELL WILSON, ET AL.

It is hereby certified that error appears in the printed specification of the above numbered patent requiring correction as follows: Page 2, second column, line 53, claim 11, after the word "normally" insert liquid; and that the said Letters Patent should be read with this correction therein that the same may conform to the record of the case in the Patent Office,

Signed and sealed this 20th day of July, A. D. 1937.

Henry Van Arsdale (Seal) Acting Commissioner of Patents.

2,08 0,681.Jesse MOTOR FUEL. December 13, 1940, by the ass DISCLAIMER Russell Wilson, Chicago, 111., and Vanderveer V0 Patent dated May 18, 1937.

orhees, Hammond, Disclaimer filed ignee, Standard Oil Company (Indiana). Hereb enters this disclaimer to claims 6, 9, 10,'and 11 in said specification.-

({ficlal Gazette January 21, 1.941.] 4 

